B.Test Procedure

2.Mold two 4 × 8-inch
test specimens as near as practical to the place where they are to be stored.
If it is not practical to mold the specimens where they will be stored, move
them to the place of storage immediately after strike off. Place molds on a
rigid surface free from vibration and other disturbances. Ensure that the
supporting surface is level to within 0.25 inch per foot.

3.Fill the specimen
molds in 1 lift poured using a suitable container without vibration, rodding,
or tapping.

4.Strike off the
surface of the concrete level with the top of the mold using a float or trowel.

5.Immediately after
molding and finishing, cap the specimens with a plastic cylinder lid or cover
with a plastic bag. Store for a period up to 24 hours at a minimum temperature
of 60 °F.

6.Before subjecting the
specimens to sawing, ensure that they have been cured for a minimum curing
period of 24 hours or have attained a minimum compressive strength of 900
pounds per square inch according to AASHTO T 22.

7.Saw specimens
lengthwise down the center. If a specimen cannot be satisfactorily sawed smooth
due to lack of curing, then do not disturb the remaining specimens for an
additional minimum curing period of 24 hours.

8.Make a visual
assessment of the cut planes of the hardened concrete cylinder or core using
the criteria in the table below. Wet the cut planes to facilitate visual
inspection.

HVSI

Criteria

0,
Stable

No
mortar layer at the top of the cut plane and no variance in size and percent
area of coarse aggregate distribution from top to bottom. (Figure 1)

1,
Stable

No
mortar layer at the top of the cut plane but slight variance in size and
percent area of coarse aggregate distribution from top to bottom.

2,
Unstable

Slight
mortar layer, less than 1 inch tall, at the top of the cut plane and distinct
variance in size and percent area of coarse aggregate distribution from top
to bottom.

3,
Unstable

Clearly
segregated as evidenced by a mortar layer greater than 1 inch tall and/or
considerable variance in size and percent area of coarse aggregate
distribution from top to bottom. (Figure 2)